Control of weeds with 0,0-dialkyl-s-morpholinocarbonylmethyl-thiophosphates and dithiophosphates

ABSTRACT

Phosphates and Thiophosphates containing a special morpholino or isomorpholino residue and having insecticidal, acaricidal and herbicidal properties are disclosed.

United States Patent [191 Beriger Apr. 30, 1974 CONTROL OF WEEDS WITH [58] Field of Search 71/87 0,0-DIALKYL-S- MORPHOLINOCARBONYLMETHYL- [56] References Cited THIOPHOSPHATES AND UNITED STATES PATENTS DITHIOPHOSPHATES 3,102,023 8/1963 Speziale et al..... 71/87 [75] Inventor: Ems Beriger, Neuanschwil, 2,959,610 11/1960 Young et a1. 260/461 Switzerland 3,134,801 5/1964 Shering et a] 260/461 [73] Assignee Ciba Geigy AG FOREIGN PATENTS OR APPLICATIONS 436,831 11/1967 Switzerland 71/87 [22] Filed: Jan. 17, 1972 [2]] A l No 218,540 Primary ExaminerLewis Gotts Assistant Examiner-Catherine L. Mills Related Apphcatlon Data Attorney, Agent, or Firm-I-Iarry Goldsmith [62] Division of Ser. No. 815,522, April 8, 1969, Pat. No.

3,658,800 57 ABSTRACT [30] Foreign Application Priority Data Phosphates and Thiophosphates containing a special morpholino or isomorpholino residue and having in- Apr. 16, 1968 Switzerland 5552/68 Secticidal, acaricida! and herbicidal properties are diS 52 us. Cl. 71/87 [51] Int. Cl A01n 9/36 8 Claims, No Drawings CONTROL OF WEEDS wrrn 0,0-D lALKYL-S MORPHOLINOCARBONYLMETHYL- THIOPHOSPHATES AND DITHIOPHOSPHATES This is a division of application Ser. No. 815,522 filed on April 8, 1969, now US. Pat. No. 3,658,800.

The present invention relates to pesticidal preparations for destroying insects, nematodes and arachnoids (mites, spider mites and ticks) and for controlling grassy weeds and other weeds in important plant cultures, among them also cultures of monocotyledonous plants, in the precmergent and the post-emergent treatment. The new preparations contain, in addition to an active ingredient, one or more of the following additives: a vehicle, a solvent, a diluent, a dispersant, an emulsifier, a thickener, an adhesive, a wetting agent and/or a fertilizer and/or further pesticides.

The active ingredients concerned are compounds of the general formula will in which R and R each represent an alkyl group having one to four carbon atoms, X represents an oxygen or sulphur atom, R represents one of the following sixmembered heterocycles containing two hetero atoms:

(in which Y represents an oxygen or sulphur atom) and R represents hydrogen or a methyl group.

Some of the active substances are new, and the invention includes these as well.

0,0-dimethyl-S morpholino-carbamoylmethyldithiophosphate is, for example, a known compound which was observedto have a good insecticidal activity. However, surprisingly the new compounds have a brader activity spectrum against animal pests, especially insofar as their systemic activity is concerned. The amount in which they have to be applied for'use as insecticides on plants is small; only when greater amounts, such as about 2 kg per hectare, are applied, can the selective herbicidal activity be clearly seen, especially in the case of those compounds in which R represents the iso(thio)morpholine residue (a).

On the other hand, the insecticidal, acaricidal and nematocidal activity is equally good with all compounds of the formula l, independently of the meaning of the substituent R and of whether X represents oxygen or sulphur. I

The toxicity towards warm-blooded animals of the compounds is satisfactorily low; thus, the compound No. ll referred to below has an oral toxicity towards the rat of LD mg per kg bodyweight.

Among animal pests of the classes Hexapoda and Ar achnoidea, there may be mentioned, for instance, the following orders and suborders: Musca, Aphis, Orgyia, Prodenia, Epilachna, Locusta, Rhipicephalus, Dermanyssus, Tetranychus, Aedes, blowfly and all development stages of insects that attack stores, including egg clusters. This enumeration is not complete, but merely emphasizes the most important types of harmful insects and Arachnoidea.

The compounds of the formula I can be manufactured by reacting an a-halocarboxylic acid halide or ester in either order with a l,3- or l,4-oxazan or 1,3 or l,4-thiazan and with a dialkyl thiophosphate or dithiophosphate.

In pesticidal preparations and for handling in practice, the new compounds may be in the form of granulates, dusting agents, emulsion concentrates, dispersions or sprays, as for instance for the gas phase application in greenhouses, or as solutions or suspensions in the usual formulation, as described in US. Pat. No. 3,329,702, British Specification 1,047,644 or Swiss Specification 424,359, some examples of which are given below. When using the preparation against animal pests, the use of baits is likewise possible.

The following Examples illustrate the invention, the parts being by weight.

EXAMPLE 1 38.3 Parts of N-chloroacetyl-Z,6-dimethyl-l ,4- oxazan (b.p. 108C under 0.08 mm Hg; prepared in the usual manner by reaction of chloroacetylchloride with 2,6-dimethyl-l,4-oxazan) were stirred with 39 parts of potassium-dimethyldithiophosphate in 260 parts by volume of acetone overnight at room temperature. The reaction mixture was worked up by suctioning off the salts, evaporating the acetone under vacuum and taking up the residue in methylenechloride. The methylenechloride solution was washed with water and then with sodium hydrogencarbonate solution and the solvent was expelled under vacuum at 50C, to leave, as residue, 51 parts of the compound of the formula ll (CHaO)zP-SCH2CON in the form of a faintly yellowish oil [Compound N0. 1]

weremanufactured in a similar manner:

The following thiolophosphates and dithiophosphates of the formula were manufactured in a similar manner:

Com-

pound R R, Physical constants No.

CH, iso-C H 11,," |.53l0

The following thiolophosphates and dithiophosphates of the formula were manufactured in a similar manner:

Physical constants OOOO COOOOO rd mammals:

mmmccazzzlrommmm N Examples of Formulation Dusting agent Equal parts of an active substance of this invention and of precipitated silicic acid were finely ground together. By mixing this powder with kaolin or talcum, a dusting agent preferably containing 1 to 6 percent of active substance can be manufactured. Spray powder In order to manufacture a spray powder, for example, the following ingredients are mixed and finely ground together:

50 parts of active substance of this invention 50 parts of Hisil (highly absorptive silicic acid) 25 parts of bolus alba (kaolin) 3.5 parts of an adduct of p-tertiary octylphenol with ethylene oxide parts of sodium l-benzyl-2-stearylbenzimidazole- 6,3'-disulphonate. Emulsion concentrate Readily soluble active substances can also be formulated as emulsion concentrates in the following manner:

20 parts of active substance parts of xylene and 10 parts of mixture of calcium dodecylbenzenesulphonate and an adduct of an alkylphenol with ethylene oxide are mixed. When this mixture is diluted with water to the desired concentration, an emulsion ready for spraying is obtained.

EXAMPLE 2 a. Activity against ticks (Rhipicephalus bursa) Testing method: 10 Ticks are dipped for 1 minute in a glass tube containing the emulsified active substance in different concentrations, then the liquid is sucked off and the residue kept for a fortnight. A percent lethal effect was recorded with the following concentrations:

Compound No. Concentration in ppm 1 2 l0 4 I00 5 l0 ll 50 12 100 b. Activity against mites (Dermanyssus gallinae) Ten to 20 mites per tube were tested as described for the tick test. The value of the concentration of the active substance in the following table represents the minimum content for a 100 percent lethal effect against the mites tested after 3 days:

Compound No. Concentration in ppm 2 ll l0 EXAMPLE 3 Activity against Lucilia sericata (larvae) A dilution series was prepared with the emulsifiable preparation of an active substance of the formula I. 2 ml ofone concentration were mixed in a glass vessel of 10 ml capacity with 2 g of chopped horse meat, and 20 to 30 freshly hatched larvae were introduced into this vessel. Evaluation was carried out 24 hours later. The indicated concentration in ppm produces a 100 lethal effect within 24 hours:

Compound No. Concentration in ppm 2 24 S 50 ll 12 EXAMPLE 4 l. Contact effect against Musca domestica (L.)

One half each of a Petri dish was treated with 1 ml each of an acetonic solution of compound No. 12, containing 200 to 100 ppm respectively of the active substance. The solvent was then evaporated and deepcooled houseflies introduced into the prepared Petri dishes and the lids were put on. Each dish contained 10 test flies. After increasing intervals of time, the lethal effect for each concentration was checked. Both concentrations displayed a 100 percent lethal effect after 8 hours.

2. Stomach poison effect against Musca domestica (L.)

In order to test the effect of the preparations as stomach poisons against houseflies, specimens of a saturated sugar solution with the emulsified active substance No. 12 were prepared so that two concentrations of 3333 EXAMPLE 1. Tests with larvae of Orgyia gonostigma and Epilachna varivestis Young Phaseolus plants are immersed in aqueoussolutions containing 800 ppm of active substance, allowed to dry and then infested with five larvae of Epilachna varivestis in the L-4 stage, whereupon the whole plant is covered with a plastic bag. The same kind of test is carried out with 5 larvae each of Orgyia gonostigma in the L3 stage and with young mallow plants. The following results were obtained:

Lethal effect at a concentration of 0.08 percent of active substance Compound No. Larvae after Lethal effect 12 Orgyia 5 days 100 2 Epilachna 5 days* 100 after 2 days removed from the aged layer EXAMPLE 6 Activity against Aphis fabae A. The aphicidal effect of the preparation was tested against Aphisfabae (S.) on the test plant Vicia faba, with the use of aqueous emulsions of the active compound N0. 11 in concentration series of 800 to 100 ppm in various ways.

In the contact test, the solution was sprayed all over the infested plant using an atomizer of the type used in chromatography. This test was evaluated 2 days later by counting the killed and the surviving aphids under a hand-held magnifying lens. All animals were then removed, and the plants reinfested with a new population. 5 Days after spraying another evaluation was carried out.

B. In order to test the penetration effects, plants were used whose leaves were as far as possible at right angles to the shoot, and the aphids were localised mainly on the underside of the leaves. In this case, spraying was not carried out all over, but vertically from above on to the plants. The penetration test was evaluated '2 days later. The effect against Aphis fabae is summarised in the following Table, in which the lethal effect is shown in percent:

Pene- Compound No. Concentration Contact Contact tration [ppm] 2 Days 5 Days 2 Days 800 100 I00 I00 400 100 80 100 200 I00 80 I00 I00 I00 0 60 800 100 100 100 400 100 100 100 15 200 100 80 I00 I00 I00 0 60 Similar results were obtained with.compounds 1 and 5.

EXAMPLE 7 a. Activity against red spider mites (Tetranychus urticae) Dwarf beans in the two-leaf stage were infested with red spider mites 24 hours before being treated with the active substance, by placing infested pieces of leaves of the grown plants upon the test plants. The treatment of the infested test plants consisted of spraying with the emulsified active substance by means of an atomizer as used in chromatography. 2 Days later, the plants were inspected with binoculars and the number of mites killed was calculated in percent. The effect of compound No. 2 on adults after 7 days in a concentration of 0.08 percent was 100 percent lethal. Similar results were obtained with the other compounds mentioned in Example 1.

EXAMPLE 8 In order to test the effect against various pests attacking stores, 5 g each of one of the compounds of the formula I were mixed with 95 g of talcum and very finely ground. In use, this dusting powder produced the following results:

Minimum concentration for 100 death in 24 hours exposure time (rng active material per Test Species of Pests (Tenebrio molitor) Larvae EXAMPLE 9 In the greenhouse test for the selective herbicidal activity in the pre-emergent process, the following plants were sown: Digitaria (crab grass), Panicum (finger grass), Alopecurus (foxtail), Avena (oats), Zeo (maize), Beta (sugar beet), Linum (flax), Brassica (cabbage rape), Soja (soybean) and Gossypium (cotton).

One day after seeding, the pots were treated with the substances Nos. 12, 13 and 14 of this invention, the quantity applied being equal to 2.5 kg of active substance per hectare. The means values from 3 compounds 21 days after treatment were:

Test plants Rating Plant species Digitaria 8-9 unplanted Panicum 9 Do.

. Alopecurus 9 7 Do.

Avena 1-2 cultivated Zea 1-2 Do. Beta l2 Do. Linum Brassica 2 Do. Soja 1 Do. Gossypium 1 Do.

l. A herbicidal preparation which comprises (1) as active ingredient an effective amount of a compound of the formula wherein each of R and R represents alkyl of from one to four carbon atoms, R represents R represents hydrogen or methyl, and X represents oxygen or sulfur and (2) a suitable carrier.

2. A method for combatting undesirable weeds which comprises applying thereto a herbicidally effective amount of a compound of the formula wherein each of R and R represents alkyl of from one to four carbon atoms, R represents R represents hydrogen or methyl, and X represents oxygen or sulfur.

3. A method according to claim 2 in which, in the formula, R is .95 4. A method according to claim 3 in which each of R and R is ethyl, R is hydrogen, and X is sulfur.

5. A method according to claim 2 in which, in the formula, R is 

2. A method for combatting undesirable weeds which comprises applying thereto a herbicidally effective amount of a compound of the formula
 3. A method according to claim 2 in which, in the formula, R3 is
 4. A method according to claim 3 in which each of R1 and R2 is ethyl, R4 is hydrogen, and X is sulfur.
 5. A method according to claim 2 in which, in the formula, R3 is
 6. A method according to claim 5 in which each of R1 and R2 is methyl, R4 is hydrogen, and X is sulfur.
 7. A method according to claim 5 in which each of R1 and R2 is ethyl, R4 is hydrogen, and X is sulfur.
 8. A method according to claim 5 in which each of R1 and R2 is ethyl, R4 is hydrogen, and X is oxygen. 